I have a 2001 Chevy Silverado with a 4.8. I have read all over the internet about the piston slap/lifter tick but no one seems to know for sure what it is. I don't think it's piston slap on my truck or at least I think it is weird that only one piston would have this problem. My guess is that one of my lifters is loosing its prime and ticking until the oil thins out. Anyway, I am going to replace the lifters and cam. Only mods are a Hypertech Programmer (Just to get rid of governer), K/N air filter in stock box, everything else is stock. This truck is not a racers by any means, I have a drag car for that. I just want a cam/lifter kit that can be installed without exhaust/intake upgrades. New to the newer model engines and wanted some opinions.